[
Genesis 6:2 KJV] 2 That the sons of God [Ben Elohim] saw the daughters of men that they [were] fair; and they took them wives of all which they chose.
[
Job 1:6 KJV] 6 Now there was a day when the sons of God [Ben Elohim] came to present themselves before the LORD, and Satan came also among them.
[
Job 38:7 KJV] 7 When the morning stars sang together, and all the sons of God [Ben Elohim] shouted for joy?
[
Daniel 3:25 KJV] 25 He answered and said, Lo, I see four men loose, walking in the midst of the fire, and they have no hurt; and the form of the fourth is like the Son of God [Bar Ela; Aramaic].
There are other places where the idea is used to describe a relationship, like the relationship between God and David described as a father-son relationship, or that of God and Adam, but in the O.T. that expression is used
exclusively for angelic beings.
Then, it comes the Christ, where God actually uses those term on him on
Psalms 2, for example. So, when the O.T. reader reads that, it is like "Wow, who is this
man who God calls
Son like that?"
[
Luke 1:32, 35 KJV] 32 He shall be great, and shall be called the
Son of the Highest: and the Lord God shall give unto him the throne of his father David: ... 35 And the angel answered and said unto her, The
Holy Ghost shall
come upon thee, and the power of the Highest
shall overshadow thee: therefore also that holy thing which shall be born of thee shall be called the
Son of God.
I know it may sound shocking to many, but there is no doubt in my opinion what it is.
Regarding the case of
Gen 6 being mere men, when was a group of men prohibited from marrying other daughters of men? The text gives no doubt of what's going on, and the sense that it was a problem, and that the "daughter of men" phrase is presented as a contrast to "sons of God", and the point of contrast is obviously of "kind" when the phrase "of men" and "of God" is used, not in a "spiritual" sense.
From the literary standpoint, I see no room to think otherwise. From the theological standpoint, some have a hard time reconciling it with other phrases like Jesus speaking about marriage and angels. I think the explanation that it was rebelious angels leaving their place and role and trying to mingle with men and doing pseudo-miracles is more plausible and in line with the text than the alternative that fights against the text, and presents new theological challenges that are harder to reconcile.